Auto merge of #16489 - jdm:http-response, r=asajeffrey
Auto merge of #16489 - jdm:http-response, r=asajeffrey

Show HTTP response headers in debug output.

- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [x] These changes do not require tests because they are changing informative debug output.

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